U.S. patent application number 11/550202 was filed with the patent office on 2007-06-21 for sensor system for a positive displacement pump.
Invention is credited to Joe Hubenschmidt, Jean-Louis Pessin, Erik Rhein-Knudsen, Nathan St. Michel, Toshimichi Wago.
Application Number | 20070139211 11/550202 |
Document ID | / |
Family ID | 38172779 |
Filed Date | 2007-06-21 |
United States Patent
Application |
20070139211 |
Kind Code |
A1 |
Pessin; Jean-Louis ; et
al. |
June 21, 2007 |
SENSOR SYSTEM FOR A POSITIVE DISPLACEMENT PUMP
Abstract
A positive displacement pump is provided that includes a pump
housing having a pump chamber; a plunger mounted in the pump
housing for reciprocating motion in the pump chamber; a suction
valve positioned to allow a fluid to enter the pump chamber upon
movement of the plunger in a first direction; a discharge valve
positioned to discharge the fluid from the pump chamber upon
movement of the plunger in a second direction; and at least one
sensor enclosed by the pump housing for measuring at least one pump
condition parameter.
Inventors: |
Pessin; Jean-Louis;
(Houston, TX) ; Hubenschmidt; Joe; (Sugar Land,
TX) ; Rhein-Knudsen; Erik; (La Baule, FR) ;
Wago; Toshimichi; (Houston, TX) ; St. Michel;
Nathan; (Houston, TX) |
Correspondence
Address: |
SCHLUMBERGER TECHNOLOGY CORPORATION
IP DEPT., WELL STIMULATION, 110 SCHLUMBERGER DRIVE, MD1
SUGAR LAND
TX
77478
US
|
Family ID: |
38172779 |
Appl. No.: |
11/550202 |
Filed: |
October 17, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11312124 |
Dec 20, 2005 |
|
|
|
11550202 |
|
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Current U.S.
Class: |
340/679 |
Current CPC
Class: |
F04B 2201/0201 20130101;
F04B 47/00 20130101; F04B 49/22 20130101; F04B 19/22 20130101; E21B
47/009 20200501; F04B 9/00 20130101; F04B 2201/0603 20130101; F04B
51/00 20130101 |
Class at
Publication: |
340/679 |
International
Class: |
G08B 21/00 20060101
G08B021/00 |
Claims
1. A positive displacement pump, comprising: a pump housing having
a pump chamber; a plunger mounted in the pump housing for
reciprocating motion in the pump chamber; a suction valve
positioned to allow a fluid to enter the pump chamber upon movement
of the plunger in a first direction; a discharge valve positioned
to discharge the fluid from the pump chamber upon movement of the
plunger in a second direction; and at least one sensor enclosed by
the pump housing for measuring at least one pump condition
parameter.
2. The pump of claim 1, further comprising a control system in
communication with the at least one sensor to process the at least
one pump condition parameter measured by the at least one sensor
for evaluating a condition of the pump.
3. The pump of claim 2, wherein the communication between the
control system and the at least one sensor is wireless.
4. The pump of claim 1, wherein the at least one sensor is self
powered.
5. The pump of claim 1, wherein the at least one sensor comprises a
chamber pressure sensor mounted on a face of the plunger at a
position adjacent to the pump chamber.
6. The pump of claim 5, wherein the chamber pressure sensor
measures at least one of pressure, temperature and vibration.
7. The pump of claim 5, wherein the chamber pressure sensor is
powered by energy from the reciprocating motion of the plunger.
8. The pump of claim 1, wherein the at least one sensor comprises a
plunger sensor carried by the plunger.
9. The pump of claim 8, wherein the plunger sensor measures a
position of the plunger.
10. The pump of claim 8, wherein the plunger sensor is powered by
energy from the reciprocating motion of the plunger.
11. The pump of claim 1, wherein the at least one sensor comprises
a pump housing sensor carried by an interior wall of the pump
housing at a position adjacent to the pump chamber.
12. The pump of claim 11, wherein the pump housing sensor measures
at least one of pressure, temperature and vibration.
13. The pump of claim 11, wherein the pump housing sensor is
powered by stress from the fluid within the pump chamber.
14. The pump of claim 1, wherein one of the suction valve and the
discharge valve comprises a flexible valve insert, and wherein the
at least one sensor comprises a valve insert sensor that measures a
degradation of the valve insert.
15. The pump of claim 14, wherein the valve insert sensor is
embedded within the flexible valve insert.
16. The pump of claim 14, wherein the valve insert sensor measures
a conductivity between itself and a valve seat.
17. The pump of claim 14, wherein the valve insert sensor measures
an integrity of itself.
18. The pump of claim 1, wherein the suction valve is movable into
and out of contact with a suction valve seat; and wherein the
discharge valve is movable into and out of contact with a discharge
valve seat, and wherein the at least one sensor comprises a valve
seat sensor that measures a degradation of one of the suction valve
seat and the discharge valve seat.
19. The pump of claim 18, wherein the valve seat sensor is embedded
within one of the suction valve seat and the discharge valve
seat.
20. The pump of claim 18, wherein the valve seat sensor measures a
conductivity between itself and one of the suction valve and the
discharge valve.
21. The pump of claim 18, wherein the valve seat sensor measures an
integrity of itself.
22. A positive displacement pump, comprising: a pump housing having
a pump chamber; a plunger mounted in the pump housing for
reciprocating motion in the pump chamber; a suction valve
positioned to allow a fluid to enter the pump chamber upon movement
of the plunger in a first direction; a discharge valve positioned
to discharge the fluid from the pump chamber upon movement of the
plunger in a second direction; at least one sensor enclosed by the
pump housing for measuring at least one pump condition parameter;
and a control system in communication with the at least one sensor
to process the at least one pump condition parameter measured by
the at least one sensor for evaluating a condition of the pump,
wherein the communication between the control system and the at
least one sensor is wireless.
23. The pump of claim 22, wherein the at least one sensor comprises
a chamber pressure sensor mounted on a face of the plunger at a
position adjacent to the pump chamber to measure at least one of
pressure, temperature and vibration, and wherein the chamber
pressure sensor is powered by energy from the reciprocating motion
of the plunger.
24. The pump of claim 22, wherein the at least one sensor comprises
a plunger sensor carried by the plunger to measure a position of
the plunger, and wherein the plunger sensor is powered by energy
from the reciprocating motion of the plunger.
25. The pump of claim 22, wherein the at least one sensor comprises
a pump housing sensor carried by an interior wall of the pump
housing at a position adjacent to the pump chamber to measure at
least one of pressure, temperature and vibration, and wherein the
pump housing sensor is powered by stress from the fluid within the
pump chamber.
26. The pump of claim 22, wherein one of the suction valve and the
discharge valve comprises a flexible valve insert, and wherein the
at least one sensor comprises a valve insert sensor that measures a
degradation of the valve insert.
27. The pump of claim 26, wherein the valve insert sensor is
embedded within the flexible valve insert, and wherein the valve
insert sensor measures a conductivity between itself and a valve
seat.
28. The pump of claim 26, wherein the valve insert sensor measures
an integrity of itself.
29. The pump of claim 22, wherein the suction valve is movable into
and out of contact with a suction valve seat; and wherein the
discharge valve is movable into and out of contact with a discharge
valve seat, and wherein the at least one sensor comprises a valve
seat sensor that measures a degradation of one of the suction valve
seat and the discharge valve seat.
30. The pump of claim 28, wherein the valve seat sensor is embedded
within one of the suction valve seat and the discharge valve seat,
and wherein the valve seat sensor measures a conductivity between
itself and one of the suction valve and the discharge valve.
31. The pump of claim 28, wherein the valve seat sensor measures an
integrity of itself.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and is a
Continuation-In-Part of U.S. patent application Ser. No.
11/312,124, filed on Dec. 20, 2005, which is incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to a sensor system
for use in a positive displacement pump, and more particularly to
such a sensor system mounted within the positive displacement
pump.
BACKGROUND
[0003] Generally, positive displacement pumps, sometimes referred
to as reciprocating pumps, are used to pump fluids in a variety of
well applications. For example, a reciprocating pump may be
deployed to pump fluid into a wellbore and the surrounding
reservoir. The reciprocating pump is powered by a rotating
crankshaft which imparts reciprocating motion to the pump. This
reciprocating motion is converted to a pumping action for producing
the desired fluid.
[0004] A given reciprocating pump may include one or more pump
chambers that each receive a reciprocating plunger. As the plunger
is moved in one direction by the rotating crankshaft, fluid is
drawn into the pump chamber through a one-way suction valve. Upon
reversal of the plunger motion, the suction valve is closed and the
fluid is forced outwardly through a discharge valve. The continued
reciprocation of the plunger continues the process of drawing fluid
into the pump and discharging fluid from the pump. The discharged
fluid can be routed through tubing to a desired location, such as
into a wellbore.
[0005] As is often the case with large systems and industrial
equipment, regular monitoring and maintenance of positive
displacement pumps may be sought to help ensure uptime and increase
efficiency. Accordingly, a need exist for an improved monitoring
system for a positive displacement pump.
SUMMARY
[0006] In one embodiment, the present invention is a positive
displacement pump that includes a pump housing having a pump
chamber; a plunger mounted in the pump housing for reciprocating
motion in the pump chamber; a suction valve positioned to allow a
fluid to enter the pump chamber upon movement of the plunger in a
first direction; a discharge valve positioned to discharge the
fluid from the pump chamber upon movement of the plunger in a
second direction; and at least one sensor enclosed by the pump
housing for measuring at least one pump condition parameter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] These and other features and advantages of the present
invention will be better understood by reference to the following
detailed description when considered in conjunction with the
accompanying drawings wherein:
[0008] FIG. 1 is a schematic illustration of a pumping system for
use in a well operation according to one embodiment of the present
invention;
[0009] FIG. 2 is a schematic illustration of a various sensors
coupled to a control system for use in the pumping system of FIG.
1;
[0010] FIG. 3 is a cross-sectional view of a positive displacement
pump that can be used in the system illustrated in FIG. 1,
according to an embodiment of the present invention;
[0011] FIG. 4 is close up view taken from detail 4 of FIG. 3,
showing the interaction of a valve with a valve seat; and
[0012] FIG. 5 is close up view of the valve and valve seat of FIG.
4 shown with degradation of both the valve and the valve seat.
DETAILED DESCRIPTION
[0013] In the following description, numerous details are set forth
to provide an understanding of the present invention. However, it
will be understood by those of ordinary skill in the art that the
present invention may be practiced without these details and that
numerous variations or modifications from the described embodiments
may be possible.
[0014] As such in FIGS. 1-5 embodiments of the present invention
relate to a system and methodology for providing optimal use of a
positive displacement pump deployed, for example, in a well related
system. In one aspect, a sensor system is located within the
positive displacement pump to detect vital pump condition
parameters. These parameters can be transferred to a control system
at the surface of the well, which can interpret the parameters and
determine the pump's condition. This control system can also
predict when maintenance or part replacements are needed.
[0015] In one embodiment, the sensor system includes one or more
sensors that are self powered using the pump motion, the pump
vibration, or another appropriate energy source from the pump, as a
power source. As used herein, a self-powered device is a device
powered by a means other than a battery or an external power cord.
For example, a self powering mechanism of a sensor according to the
present invention may include a magnet-coil assembly or a
piezoelectric material, among other appropriate self powering
mechanisms.
[0016] In one embodiment described herein, the sensor system is
used to obtain data on pump condition parameters that indicate
abnormal events during pumping or degradation of suction valves
and/or discharge valves within the pump. The determination of valve
wear can be indicative of a failure mode, and the data can be used
in predicting failure of the component. Examples of abnormal events
that occur during pumping include pump cavitation, loss of prime,
valves stuck in an open or closed position, and debris interfering
with valve closure.
[0017] Referring generally to FIG. 1, a system 20 is illustrated
for use in a well application, according to one embodiment of the
present invention. It should be noted that the present system and
method can be used in a variety of applications. As such, the
illustrated well application is merely used as an example to
facilitate explanation. In the illustrated embodiment, the system
20 includes, for example, a positive displacement pump, i.e. a
reciprocating pump 22, deployed for pumping a fluid into a well 24
having a wellbore 26 drilled into a reservoir 28 containing
desirable fluids, such as hydrocarbon based fluids.
[0018] In many applications, the wellbore 26 is lined with a
wellbore casing 30 having perforations 32 through which fluids can
flow between the wellbore 26 and the reservoir 28. The
reciprocating pump 22 may be located at a surface location 34, such
as on a truck or other vehicle 35, to pump fluid into the wellbore
26 through the tubing 36 and out into the reservoir 28 through the
perforations 32. By way of example, the well application may
include pumping a well stimulation fluid into the reservoir 28
during a well stimulation operation, e.g. pumping a fracturing
fluid into the well.
[0019] In the embodiment illustrated in FIG. 1, the positive
displacement pump 22 is coupled to a control system 40 by one or
more communication lines 42. The communication line(s) 42 can be
used to carry signals between the positive displacement pump 22 and
the control system 40. For example, data from sensors located
within the pump 22 can be output through communication lines 42 for
processing by control system 40. The form of communication lines 42
may vary depending on the design of the communication system. For
example, the communication system may be formed as a hardwired
system in which communication lines 42 are electrical and/or
fiber-optic lines.
[0020] Alternatively, the communication system may include a
wireless system in which communication lines 42 are wireless and
able to provide wireless communication of signals between the pump
sensors and the control system 40. An advantage of the wireless
communication system is that it lacks wires, which if present could
be inadvertently moved and/or dislodged from a desired location due
to human interaction or due to movements or vibrations caused by
the mere operation of the pump.
[0021] Referring to FIG. 2, the control system 40 may be a
processor based control system able to process data received from a
sensor system 44 deployed within the pump 22. By way of example,
the control system 40 may be a computer-based system having a
central processing unit (CPU) 46. In one embodiment, the CPU 46 is
operatively coupled to a memory device 48, as well as an input
device 50 and an output device 52. The input device 50 may include
a variety of devices, such as a keyboard, a mouse, a
voice-recognition unit, a touch-screen, among other input devices,
or combinations of such devices. The output device 52 may include a
visual and/or audio output device, such as a monitor having a
graphical user interface. Additionally, the processing may be done
on a single device or multiple devices at the well location, away
from the well location, or with some devices located at the well
and other devices located remotely.
[0022] The sensor system 44 is designed to detect specific
parameters associated with the operation of the positive
displacement pump 22. Data related to the specific parameters is
output by the sensor system 44 through communication line or lines
42 to the control system 40 for processing and evaluation (note
again that in one embodiment this communication is wireless.) The
pump parameter data is used to determine possible failure modes
through indications of pump malfunctions, such as pump component
degradations, e.g. pump valve or valve seat degradation.
[0023] The control system 40 also can be used to evaluate and
predict an estimated time to failure using techniques, such as data
regression. As will be explained more fully below, the sensor
system 44 may include one or more sensors located within the
positive displacement pump 22. Examples of such sensors include a
pump chamber sensor 54, a plunger sensor 55, a pump housing sensor
56, a valve insert sensor 57, and a valve seat sensor 58.
[0024] A positive displacement pump 22 according to one embodiment
of the present invention is illustrated in FIG. 3. As illustrated,
the pump 22 includes a pump housing 62 having a pump chamber 64. A
plunger 66 is slidably mounted within pump housing 62 for
reciprocating motion within the pump chamber 64. The reciprocating
motion of the plunger 66 acts to change the volume of the pump
chamber 64. The pump 22 further includes check valves, such as a
suction valve 68 and a discharge valve 70, that control the flow of
fluid into and out of the pump chamber 64 as the plunger 66
reciprocates.
[0025] The reciprocating motion of the plunger 66 may be generated
by a rotating crankshaft (not shown), as known to those of ordinary
skill in the art. It should also be noted that a single plunger and
a single pump chamber are illustrated to facilitate explanation.
However, the illustrated single plunger and single pump chamber
also are representative of potential additional plungers and pump
chambers along with their associated check valves. For example, the
illustrated single plunger and single pump chamber may form a
portion of a three chamber, triplex pump. With a triplex pump or
other multiple chamber pumps, the motion of the plungers can be
staggered to achieve a more uniform flow of pumped fluids, making
such pumps desirable in a number of pumping applications.
[0026] The suction valve 68 and the discharge valve 70 are actuated
by fluid and spring forces. The suction valve 68, for example, is
biased toward a suction valve seat 72, i.e. toward a closed
position, by a spring 74 positioned between the suction valve 68
and a spring stop 76. Similarly, the discharge valve 70 is biased
toward a discharge valve seat 78, i.e. toward a closed position, by
a discharge valve spring 80 positioned between the discharge valve
70 and a spring stop 82.
[0027] As shown, the suction valve 68 further includes a sealing
surface 84 oriented for sealing engagement with the valve seat 72.
The sealing surface 84 of the valve 68 includes a strike face 86,
that may be formed of a metal, and a flexible portion that may be
formed as a flexible valve insert 88. The flexible valve insert 88
may be slightly raised relative to the strike face 86.
[0028] Similarly, the discharge valve 70 includes a sealing surface
90 oriented for sealing engagement with the valve seat 78. The
sealing surface 90 of the valve 70 includes a strike face 92, that
may be formed of a metal, and a flexible portion that may be formed
as a flexible valve insert 94. The flexible valve insert 94 may be
slightly raised relative to strike face 92.
[0029] When the plunger 66 moves outwardly (to the left in FIG. 3),
a drop in pressure is created within the pump chamber 64. This drop
in pressure causes the suction valve 68 to move against the bias of
spring 74 to an open position and causes fluid to flow into pump
chamber 64 through the suction valve 68. This phase can be referred
to as the "suction stroke." When the plunger 66 moves in a reverse
direction (to the right in FIG. 3), the suction valve 68 is closed
by the spring 74, and pressure is increased in the pump chamber 64.
The increase in pressure causes the discharge valve 70 to open and
forces fluid from the pump chamber 64 outwardly through discharge
valve 70. The discharge valve 70 remains open while the plunger 66
continues to apply pressure to the fluid in the pump chamber 64.
The high-pressure phase in which fluid is discharged through the
discharge valve 70 is known as the "discharge stroke."
[0030] As each valve 68,70 is closed, its valve insert 88,94
contacts its corresponding seat 72,78 and is compressed until the
strike face 86,92 of the valve 68,70 also makes contact with the
seat 72,78. With the suction valve 68, for example, the valve
insert 88 is compressed against the valve seat 72 until the strike
face 86 contacts the valve seat 72. This normally occurs shortly
after initiation of the discharge stroke. With the discharge valve
70, the valve insert 94 is compressed against the valve seat 78
until the strike face 92 contacts the valve seat 78. This normally
occurs shortly after initiation of the suction stroke.
[0031] The flexible valve inserts 88,94 are beneficial for
environments in which fluid containing an abrasive material, such
as sand, or other particulates is pumped. Typically, the valve
inserts 88,94 are composed of urethane or some other conventional
deformable polymer. The deformation of the flexible valve inserts
88,94 enables the valves 68,70 to seal even when fluids containing
particles, for example cement particles, sand or proppant, are
moved through the pump 22. However, the abrasive action of such
particulates during extended use of the valves 68,70 causes the
flexible valve inserts 88,94 to degrade, which reduces the ability
of the valves 68,70 to form a seal and ultimately leads to valve
failure and pump malfunction. In one embodiment, the valve inserts
88,94 are made of urethane or another conventional polymers.
[0032] However, the valve inserts 88,94 may not be necessary in
applications involving the pumping of relatively "clean" or
"non-abrasive" fluids. In such applications, the sealing surfaces
84,90 of the valves 68,70 can be formed without the valve inserts
88,94 such that sealing is accomplished only between the metal
strike face 86,92 of the valves 68,70 and the valve seats 72,78. In
embodiments where the valves 68,70 are designed without the
flexible valve inserts 88,94, the metal strike faces 86,92 of the
valves 68,70 may still degrade with repeated use, although
typically not as quickly.
[0033] As such, the sensor system 44 is incorporated into the pump
22 to detect pump condition parameters which can be used to
determine component wear or degradation, and/or other pump
malfunctions. In one embodiment, the sensor system 44 is used to
detect wear on the suction and/or discharge valves 68,70 through
the use of sensors positioned at various locations within the
positive displacement pump 22.
[0034] For example, in one embodiment the sensor system 44 includes
a pump chamber sensor 54 mounted on a face of the plunger 66 at a
position adjacent to the pump chamber 64 to allow for continued
exposure of the sensor 54 to the pump chamber 64 and the fluid
disposed therein. At such a position, the sensor 54 may measure the
pump chamber pressure, temperature and/or vibration, among other
desired parameters. Such a sensor 54 may be self powered using
energy from the motion of the plunger 66. The pump chamber sensor
54 may include any appropriate sensor, such as a pressure sensor, a
temperature sensor, or an accelerometer, among other appropriate
sensors.
[0035] The sensor system 44 may include a plunger sensor 55 mounted
on or inside the plunger 66. At such a position, the plunger sensor
55 may measure the position of the plunger 66, among other desired
parameters. Such a plunger sensor 55 may be self powered using
energy from the motion of the plunger 66. The plunger sensor 55 may
include any appropriate sensor, such as an accelerometer or a
proximity switch, among other appropriate sensors.
[0036] The sensor system 44 may include a pump housing sensor 56
mounted on or within an interior wall of the pump housing 62.
Although FIG. 3 shows two possible locations of the pump housing
sensor 56, in one embodiment the pump housing sensor 56 may be
mounted at any position along the interior wall of the pump housing
62 as long as it is adjacent to the pump chamber 64. The pump
housing sensor 56 may measure the pump chamber pressure,
temperature and/or vibration, among other desired parameters.
[0037] Note that in order to measure the pump chamber pressure, it
is advantageous for the pump housing sensor 56 to be positioned
such that it may contact fluid within the pump chamber 64. The pump
housing sensor 56 may be self powered using stress from the
energized fluid within the pump chamber 60. The pump housing sensor
56 may include any appropriate sensor, such as a pressure sensor, a
temperature sensor, or an accelerometer among other appropriate
sensors.
[0038] As shown in FIGS. 4 and 5, the sensor system 44 may include
a valve insert sensor 57 mounted on or within the flexible valve
inserts 88,94 of either or both of the valves 68,70. The valve
insert sensor 57 measures a degradation 25 (see FIG. 5) or a
wearing away of the valve insert 88,94 to which it is attached.
[0039] Typically, the valve insert 88,94 is composed of an
insulator, and the valve seat 72,78 is composed of a conductor. In
such an embodiment, the valve insert sensor 57 may be a sensor that
measures conductivity between itself and another conductor, such as
an electrical resistivity sensor or a voltage sensor, among other
appropriate sensors.
[0040] As such, in this embodiment, the valve insert sensor 57 is
embedded in the valve insert 88,94 at a position such that when the
valve insert 88,94 is not degraded (as shown in FIG. 4) or at least
when the valve insert 88,94 is degraded to an acceptable level, the
valve insert sensor 57 does not contact the valve seat 72,78 and
therefore cannot measure a conductivity therebetween; and when the
valve insert 88,94 is degraded to an undesirable level (as shown in
FIG. 5 and indicated by degraded section 25), the valve insert
sensor 57 contacts the valve seat 72,78 and measures a conductivity
therebetween. At such a time, the valve insert sensor 57 may send a
signal to the control system 40 indicating an undesirably worn
valve insert 88,94.
[0041] Additionally or in the alternative, the valve insert sensor
57 may be configured to measure a conductivity between itself and
the fluid being pumped. Such a situation occurs when the end of the
sensor 57 is exposed and in contact with the fluid being pumped,
but not yet exposed to the extend allowing the sensor 57 to contact
the valve seat 72,78.
[0042] In another embodiment, the valve insert sensor 57 measures
the integrity of itself. When the integrity is damaged to a
predetermined condition, then the control system 40 determines that
the valve insert 88,94 is undesirably worn. In either embodiment,
the valve insert sensor 57 can be self powered by the stress from
the valve insert 88,94 deformation.
[0043] As is also shown in FIGS. 4 and 5, the sensor system 44 may
include a valve seat sensor 58 mounted on or within the valves seat
72,78. The valve seat sensor 58 measures a degradation 27 (see FIG.
5) or a wearing away of the valve seat 72,78 to which it is
attached.
[0044] Typically, the valve seat 72,78 is composed of a conductor,
and the strike face 86,92 of the valve 68,70 is composed of a
conductor. In such an embodiment, the valve seat sensor 58 may be a
sensor that measures conductivity between itself and another
conductor, such as an electrical resistivity sensor or a voltage
sensor, among other appropriate sensors.
[0045] As such, in this embodiment, the valve seat sensor 58 is
encased, at least partially, in an insulator 59; and the sensor 58
and the insulator 59 are embedded in the valve seat 72,78 at a
position such that when the valve seat 72,78 is not degraded (as
shown in FIG. 4) or at least when the valve seat 72,78 is degraded
to an acceptable level, the valve seat sensor 58 does not contact
the strike face 86,92 of the valve 68,70 and therefore cannot
measure a conductivity therebetween; and when the valve seat 72,78
is degraded to an undesirable level (as shown in FIG. 5 and
indicated by degraded section 27), which is quickly followed by a
degradation of the insulator 59, the valve seat sensor 58 contacts
the valve seat 72,78 and measures a conductivity therebetween. At
such time, the valve seat sensor 58 may send a signal to the
control system 40 indicating an undesirably worn valve seat
72,78.
[0046] Additionally or in the alternative, the valve seat sensor 58
may be configured to measure a conductivity between itself and the
fluid being pumped. Such a situation occurs when the end of the
sensor 58 is exposed and in contact with the fluid being pumped,
but not yet exposed to the extend allowing the sensor 58 to contact
the strike face 86,92 of the valve 68,70.
[0047] In another embodiment, the valve seat sensor 58 measures the
integrity of itself. When the integrity is damaged to a
predetermined condition, then the control system 40 determines that
the valve insert 88,94 is undesirably worn. In either embodiment,
the valve seat sensor 58 can be self powered by the stress from the
valve seat 72,78 deformation, or the valve seat sensor 58 can be
battery powered and operated in a low-bandwidth mode.
[0048] Any one or all of the sensors 54-58 may be mounted within
the pump housing 62 (FIG. 3 shows each of the sensors 54-58 mounted
within the pump housing 62) to protect the sensors 54-58 from the
environment external to the pump housing 62 and to protect the
sensors 54-58 from inadvertent movement or dislodgement of the
sensors 54-58, such as by inadvertent human contact.
[0049] As eluded to above, any one or all of the sensors 54-58 may
communicate with the control system 40 wirelessly. Wireless
communication between the sensors 54-58 and the control system 40
lessens the likelihood of the sensors 54-58 being inadvertently
moved and/or dislodged from a desired location due to inadvertently
human contact or due to movements or vibrations caused by the mere
operation of the pump 22.
[0050] As described above, a plurality of pump parameters detected
within a positive displacement pump can be used individually or in
combination to determine indications of pump component degradation.
It should be noted that different types of sensors can be used in
pump 22, and those sensors can be located at a variety of locations
within the pump depending on, for example, pump design, well
environment and sensor capability. Additionally, the sensor or
sensors may be deployed in pumps having a single pump chamber or in
pumps having a plurality of pump chambers to provide data for
determining degradation of valves associated with each pump chamber
and/or other pump malfunctions. Note that the sensors 54-58 are
shown schematically in FIGS. 1-5 and are not necessarily drawn to
scale.
[0051] The preceding description has been presented with reference
to presently preferred embodiments of the invention. Persons
skilled in the art and technology to which this invention pertains
will appreciate that alterations and changes in the described
structures and methods of operation can be practiced without
meaningfully departing from the principle, and scope of this
invention. Accordingly, the foregoing description should not be
read as pertaining only to the precise structures described and
shown in the accompanying drawings, but rather should be read as
consistent with and as support for the following claims, which are
to have their fullest and fairest scope.
* * * * *